Updated readme

Author: btyy77c

README.md

@@ -7,6 +7,36 @@ https://firebase.google.com/docs/auth/admin/verify-id-tokens
 
 Unfortunately, it appears Google does not have support for Ruby. So, I made my own auth file!
 
-This gem is an extraction of that file and is still in development.
+## Installation:
+#### Using Rubygems:
+```
+gem install firebase-token-verify
+```
 
-If you can't wait for the gem to be finished, you're welcome to checkout the lib directory and add the code to your system as needed.
+#### Using Bundler
+Add `gem 'firebase-token-verify'` to your Gemfile and run `bundle install`
+
+## Example use-case scenario:
+1) Lookup your firebase id and add it to your Ruby code, for example: `PROJECT_ID = <your_firebase_project_id>`
+2) Obtain a user token.  You will need to be connected with JavaScript, or a mobile app, to obtain the user token. I usually obtain a user token using a JavaScript method similar to the one below:
+```sh
+user.getIdToken(true).then(token => {
+  // Send this token to your Ruby application
+})
+```
+3) Setup some Ruby code to process the token
+```sh
+require 'firebase_ruby_auth'
+
+class FirebaseRubyAuthWrapper
+  PROJECT_ID = ENV['<your_firebase_project_id>']
+
+  def initialize
+    @auth = FirebaseRubyAuth.new(PROJECT_ID)
+  end
+
+  def retrieve_email_from_token(token)
+    @auth.decode_token(token)['email']
+  end
+end
+```